Plastic beer keg

ABSTRACT

A plastic keg includes a liner including a neck portion and a body portion. A lid having an opening is disposed at least partially over the liner. A retainer is secured to the neck portion of the liner and aligned with the opening in the lid, the retainer including external threads. A locking ring having internal threads is secured to the external threads of the retainer. The internal threads of the locking ring and the external threads of the retainer include a ratcheting mechanism permitting attachment of the locking ring to the retainer and inhibiting removal of the locking ring from the retainer, the locking ring contacting the lid. A beer keg valve assembly includes a port having a head portion having a convex upper surface and at least one leg extending downwardly from a lower surface. The leg includes a stop surface projecting radially outward further than the head portion. A piston defines an opening. A spring biases the port against a periphery of the opening defined by the piston to seal the convex upper surface of the head portion over the opening.

This application claims priority to U.S. Provisional Application Ser.No. 61/411,787, filed Nov. 9, 2010.

BACKGROUND

The present invention relates to a plastic container for liquids,particularly beverages such as beer.

Most current beer kegs include a steel body with a valve in the top forboth filling the keg and for accessing the contents. The steel kegs arereusable. Empty kegs are returned and then washed and refilled in anautomated process. The steel kegs are inverted, such that the valve isat the bottom of the keg to facilitate draining during cleaning. Theinterior of the body of the keg is washed by spraying cleansing liquidsthrough the valve. The cleansing liquids wash the inner surface of thebody of the keg and then drain downward through the valve. The kegs aretypically then filled in the inverted position through the valve at thebottom of the keg. Throughout the automated process, a cylinder clampsthe body of the keg with a high force (between 200 and 300 lb.) to holdthe keg in place while the washing and filling heads connect to thevalve at the bottom of the keg.

There are several problems with the use of steel kegs. First, they arefairly heavy, even when empty. Second, they are expensive and are notalways returned by the user. If a deposit is charged to the user toensure the return of the keg, this may discourage the user from choosingto purchase beer by the keg in the first place. However, if the depositis too low, it is possible that the value of the steel in the kegexceeds the amount of the deposit, thus contributing to some kegs notbeing returned.

SUMMARY

According to one feature of the present invention, a plastic kegincludes a liner including a neck portion and a body portion. A lidhaving an opening is disposed at least partially over the liner. Aretainer is secured to the neck portion of the liner and aligned withthe opening in the lid, the retainer including external threads. Alocking ring having internal threads is secured to the external threadsof the retainer. The internal threads of the locking ring and theexternal threads of the retainer include a ratcheting mechanismpermitting attachment of the locking ring to the retainer and inhibitingremoval of the locking ring from the retainer, the locking ringcontacting the lid.

According to another feature of the present invention, which can bepracticed with or without the first feature, a beer keg valve assemblyincludes a port having a head portion having a convex upper surface andat least one leg extending downwardly from a lower surface. The legincludes a stop surface projecting radially outward further than thehead portion. A piston defines an opening. A spring biases the portagainst a periphery of the opening defined by the piston to seal theconvex upper surface of the head portion over the opening.

These and other features of the application can be best understood fromthe following specification and drawings, the following of which is abrief description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a section view of a plastic keg according to a firstembodiment of the present invention.

FIG. 2 is a perspective view of the plastic keg.

FIG. 3 is a bottom perspective view of the plastic keg.

FIG. 4 is a first side view of the plastic keg.

FIG. 5 is a second side view of the plastic keg.

FIG. 6 is a first side view of the outer container.

FIG. 7 is a second side view of the outer container.

FIG. 8 is a perspective view of the retainer.

FIG. 9 is a perspective view of the locking ring.

FIG. 10 is a perspective view of the top of the plastic keg showing thelocking ring being attached to the retainer.

FIG. 11 is a top view of the locking ring.

FIG. 12 is a section view taken along line C-C of FIG. 11.

FIG. 13 is a section view taken along line D-D of FIG. 11.

FIG. 14 is a section view taken along line F-F of FIG. 11.

FIG. 15 is a section view through the retainer and valve assembly in anormal condition.

FIG. 16 is a perspective view of the port.

FIG. 17 is a top view of the port.

FIG. 18 is a side view of the port.

FIG. 19 is a bottom view of the port.

FIG. 20 is a section view of the retainer and valve assembly, similar toFIG. 15, in an overpressure condition.

FIG. 21 is a bottom perspective view of the port and piston of FIG. 20in the overpressure condition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a section view of an assembled plastic beer keg 10 accordingto one embodiment of the present invention. The plastic beer keg 10generally includes an outer container 12 surrounding an inner liner 14,such as a PET bottle. A lid 16 is secured over an open end of the outercontainer 12 to retain the liner 14 within the interior of the outercontainer 12. A valve assembly 18 is retained in the mouth of the liner14 by a retainer 20, which protrudes through the lid 16. A tube 19extends from the valve assembly 18 to the bottom of the liner 14.

The outer container 12 includes a cylindrical outer wall 24 extendingupward from the periphery of a base 23. The outer wall 24 has anoutwardly projecting lip 26 at an upper edge thereof. A plurality oflocking ribs 27 (in this example, four) project outward from thecylindrical outer wall 24 below the lip 26.

The lid 16 includes a lip 30 extending downward from a generallyhorizontal, annular rim portion 31 extending about the periphery of thelid 16 and sealed over the lip 26 of the outer container 12. A pluralityof inwardly-projecting shoulders 33 are formed about the inner peripheryof the lip 30 of the lid 16 and are secured below the locking ribs 27 ofthe cylindrical outer wall 24.

The lid 16 further includes a lower annular wall 32 spaced below theupper edge of the outer container 12 and connected by a frustoconicalwall 34 to the outer periphery of the lid 16. A plurality of radiallyextending ribs 38 reinforce the frustoconical wall 34. The retainer 20projects through an opening defined through the center of the lid 16.

The liner 14 is a PET bottle or other suitable material having generallycylindrical side walls 42 and an upper shoulder portion 44 transitioningto a neck 50, which as shown, may be threaded.

The retainer 20 is secured to the neck 50 of the liner 14 in order toretain the valve assembly 18 within the neck 50. The retainer 20 issecured to the neck 50 of the liner 14 by a snap-fit or by threadingthat may lock in place when the threads bottom out. A fastener, in thiscase a locking ring 22, is secured to the retainer 20 to secure theretainer 20 to the lid 16. In this example, the locking ring 22 isthreaded to the retainer 20 to prevent the retainer 20 from beingremoved downwardly through the opening in the lid 16.

FIGS. 2 and 3 are exterior views of the keg 10 of FIG. 1. As shown, thewall 24 of the outer container 12 may include handle openings 40 (oneshown, but one would be on the opposite side). A skirt 28 (FIG. 2) mayextend around the periphery of the wall 24 to provide ease of handling.The outer container 12, the lid 16, and the retainer 20 may each beseparately molded of HDPE, polypropylene or other suitable materials.

FIGS. 4 and 5 are side views of the keg 10.

FIGS. 7 and 8 are side views of the outer container 12. As shown, thereare four locking ribs 27 disposed about the periphery of the outercontainer 12. As shown, the locking rib 27 angles downwardly between aleading rib 52 and a stop rib 57 that extends downward past the lockingrib 27. The lid 16 can be attached to the outer container 12 in eitherof two ways. First, with the shoulders 33 aligned with the locking ribs27, the lid 16 is then pressed down until the locking ribs 27 bias theshoulders 33 outward until the shoulders 33 snap down below the lockingribs 27, thereby locking the lid 16 to the container 12. Alternatively,the lid 16 can be placed on the container 12 with the shoulders 33 tothe counter-clockwise position of the locking ribs 27.

Referring to FIG. 8, the retainer 20 includes an annular wall 66 havingexternal threads 68. At least a portion of at least one of the externalthreads 68 is separated into a plurality of tapered ratchet teeth 69.

FIG. 9 is a perspective view of the locking ring 22. The locking ring 22includes a generally vertical annular wall 84 having interior threads 92having vertically aligned gaps 94. Teeth 93 are formed between at leastone pair of the interior threads 92.

An outer annular portion 86 curves outward and downward from a loweredge of the annular wall 84. Radially extending ribs 88 facilitaterotating the locking ring 22 by hand or with automated equipment.Locking ring tabs 90 protrude radially outwardly from the outer annularportion 86. The locking ring tabs 90 are configured so that they can bebent back or broken for disassembly after use.

Ratcheting teeth 96 are formed on the outer ends of the locking ringtabs 90. The ratcheting teeth 96 each include a tapered surface 98 toprovide the ratcheting function against the ratchet teeth 78 on theinner frustoconical wall 76 of the lid 16, as can be seen in FIG. 10.The ratcheting teeth 96 would permit the locking ring 22 to be rotatedin a tightening direction (in this case, clockwise) and prevent rotationin a loosening direction (in this case, counterclockwise). After use,the locking ring tabs 90 can be bent back or broken for disassembly andrecycling of the keg 10.

The teeth 93 (FIG. 9) in the interior threads 92 of the locking ring 22engage the tapered ratchet teeth 69 of the retainer 20 when the lockingring 22 is threaded onto the retainer 20, as shown in FIG. 10. The teeth93 and teeth 69 provide a ratchet mechanism between the locking ring 22and the retainer 20. The tapered ratchet teeth 69 permit the teeth 93 onthe locking ring 22 to rotate past to attach the locking ring 22 to theretainer 20, but do not permit the locking ring 22 to be subsequentlyremoved from the retainer 20. However, when a user seeks to remove thelocking ring 22 by rotation, this will cause the retainer 20 to rotate,thereby unscrewing the retainer 20 from the neck 50 of the liner 14.Before the retainer 20 is completely removed, the pressure in the liner14 is released through vertically aligned gaps in the interior threadsin the retainer 20 and vertically aligned gaps in the exterior threadson the neck 50 of the liner 14.

FIG. 11 is a top view of the locking ring 22. FIG. 12 is a section viewtaken along line C-C of FIG. 11. FIG. 13 is a section view taken alongline D-D of FIG. 11. FIG. 14 is a section view taken along line F-F ofFIG. 11.

A section view of the valve assembly 18 is shown in FIG. 15. A cup 54has a plurality of openings 55. A valve body 56 received in the cup 54is connected to the tube 19 and biased away from the cup 54 by an outerspring 58. A port 60 is received in the valve body 56 and biased awayfrom the valve body 56 by an inner spring 62 toward a piston 64 having aseal 65. The piston 64 is biased toward the retainer 20. The retainer 20includes an annular wall 66 having external threads 68. The annular wall66 of the retainer 20 also includes internal threads 67 that may havevertically aligned gaps which, together with gaps in the threads on theneck of the liner 14, permit the controlled release of pressure in theliner 14 when the retainer 20 is unscrewed.

The port 60 includes a convex head portion 70 and an elongated tailportion 72 extending downwardly from a lower surface thereof. Aplurality (in this example, four) of legs 74 extend downwardly from thelower surface of the head portion 70, spaced outward from the tailportion 72. Stops 75 project radially outwardly from lower ends of thelegs 74. Referring to FIGS. 16-19, the stops 75 of the port 60 projectradially outward further than the head portion 70. The head portion 70includes alternating radial projections 76 and recesses 78 about itsperiphery.

In normal operation, the head portion 70 of the port 60 is biasedagainst the seal 65 of the piston 64 thereby closing the opening definedby the port 60 as shown in FIG. 15 (and selectively biased downward awayfrom the piston 64 to access the keg 10 during use). In a significantoverpressure situation, the head portion 70 of the port 60 may be forcedinto the opening of the piston 64, as shown in FIG. 20. In that case,the stops 75 will limit the movement of the port 60 and retain the port60 in the valve assembly 18 as shown in FIG. 21. The alternatingprojections 76 on the head portion 70 will force the opening of thepiston 64 outward, thereby permitting release of pressure in the liner14 through the recesses 78 between the projections 76. This permits thepressure in the liner 14 to be released, while preventing the port 60from separating from the valve assembly 18.

In accordance with the provisions of the patent statutes andjurisprudence, exemplary configurations described above are consideredto represent a preferred embodiment of the invention. However, it shouldbe noted that the invention can be practiced otherwise than asspecifically illustrated and described without departing from its spiritor scope.

What is claimed is:
 1. A beer keg valve assembly comprising: a firstvalve member having a head portion having a convex upper surface and atleast one leg extending downwardly from a lower surface, the legincluding a stop surface projecting radially outward, the first valvemember including at least one recess formed at the periphery of the headportion; a second valve member defining an opening, wherein the at leastone recess at the periphery of the head portion of the first valvemember is configured to release pressure through the first valve memberin the event that the head portion is forced into the opening of thesecond valve member; and a spring biasing the first valve member againsta periphery of the opening defined by the second valve member to sealthe convex upper surface of the head portion over the opening.
 2. A beerkeg including the beer keg valve assembly of claim 1 and furtherincluding: a container having a base and a wall extending upward from aperiphery of the base to define a container interior, a liner disposedat least partially within the container interior, the liner including abody portion and a neck portion, the beer keg valve assembly at leastpartially disposed in the neck portion, a lid connected to the wall ofthe container over at least a portion of the liner.
 3. The beer kegvalve assembly of claim 1 wherein the first valve member includes a tailportion extending downwardly from the head portion.
 4. The beer kegvalve assembly of claim 3 wherein the at least one leg includes aplurality of legs radially outward of the tail portion, each including astop surface projecting radially outward.
 5. The beer keg valve assemblyof claim 4 wherein the spring is an inner spring and wherein the firstvalve member is urged against the second valve member by the innerspring.
 6. The beer keg valve assembly of claim 5 wherein the secondvalve member is urged against a retainer by an outer spring.
 7. The beerkeg valve assembly of claim 6 further including a seal on the secondvalve member sealing against the first valve member and against theretainer.
 8. A beer keg valve assembly comprising: a first valve memberhaving a head portion having a convex upper surface, at least one legextending downwardly from a lower surface of the head portion and thenradially outward, such that the leg includes a stop surface spaceddownwardly of the head portion; a second valve member defining anopening, wherein the first valve member includes at least one recessformed at the periphery of the head portion for releasing pressurethrough the first valve member in the event that the head portion isforced into the opening of the second valve member; and a spring biasingthe first valve member against a periphery of the opening defined by thesecond valve member to seal the convex upper surface of the head portionover the opening.
 9. The beer keg valve assembly of claim 8 wherein thefirst valve member includes a tail portion extending downwardly from acenter of the head portion further than the at least one leg.
 10. Thebeer keg valve assembly of claim 9 wherein the at least one leg includesa plurality of legs radially outward of the tail portion, each includinga stop surface spaced downwardly of the head portion.
 11. The beer kegvalve assembly of claim 10 wherein the first valve member is urgedagainst the second valve member by an inner spring.
 12. The beer kegvalve assembly of claim 11 wherein the second valve member is urgedagainst a retainer by an outer spring.
 13. The beer keg valve assemblyof claim 12 further including a seal on the second valve member sealingagainst the first valve member and against the retainer.
 14. A beer kegincluding the beer keg valve assembly of claim 13 and further including:a container having a base and a wall extending upward from a peripheryof the base to define a container interior, a liner disposed at leastpartially within the container interior, the liner including a bodyportion and a neck portion, the beer keg valve assembly at leastpartially disposed in the neck portion, a lid connected to the wall ofthe container over at least a portion of the liner.
 15. A beer keg valveassembly comprising: a first valve member having a head portion having aconvex upper surface, a plurality of legs below the head portion andextending radially outward, wherein the head portion includes at leastone recess; a second valve member defining an opening, wherein the atleast one recess in the head portion is configured to release pressurethrough the first valve member in the event that the head portion isforced into the opening of the second valve member; and a spring biasingthe first valve member against a periphery of the opening defined by thesecond valve member to seal the convex upper surface of the head portionover the opening.
 16. The beer keg valve assembly of claim 15 whereinthe first valve member includes a tail portion extending downwardly froma center of the head portion further than the plurality of legs.
 17. Thebeer keg valve assembly of claim 15 wherein each of the plurality oflegs includes a stop surface spaced downwardly of the head portion. 18.The beer keg valve assembly of claim 15 wherein the at least one recessincludes a plurality of recesses formed at a periphery of the headportion, the first valve member including the plurality of recessesalternating with a plurality of radial projections formed at theperiphery of the head portion for releasing pressure through theplurality of recesses in the event that the head portion is forced intothe opening of the second valve member.
 19. A beer keg including thebeer keg valve assembly of claim 15 and further including: a containerhaving a base and a wall extending upward from a periphery of the baseto define a container interior, a liner disposed at least partiallywithin the container interior, the liner including a body portion and aneck portion, the beer keg valve assembly at least partially disposed inthe neck portion, a lid connected to the wall of the container over atleast a portion of the liner.